Tabular and Chart DI

In tabular DI, the FIRST move is to identify what each row and column represents and the unit (actual numbers, %, ratios, or thousands/lakhs). Common SBI PO trap: mixing absolute values with percentages. Before calculating, scan whether totals are given or must be derived. Memory aid: read the QUESTION first, then return to the table — never read the whole table top-to-bottom. For 'how many %' questions, set the base correctly: 'A more than B' uses B as base = (A-B)/B x 100. For 'increase from previous year', the previous year is always the base. Underline keywords like 'at least', 'exactly', 'respectively'. Speed tip: jot derived totals in the margin so you don't recompute them across 5 linked questions.

Convert frequent fractions to percentages instantly: 1/8=12.5%, 1/6=16.67%, 1/7≈14.28%, 1/9≈11.11%, 1/11≈9.09%, 1/12≈8.33%, 3/8=37.5%, 5/8=62.5%. For percentage change use: change/original x 100. To compare two ratios a/b and c/d quickly, cross-multiply: a×d vs b×c (larger product = larger fraction). For 'what percent is X of Y', X/Y×100. To find a value when percentage and result are known, use unitary method: if 12% = 96, then 1% = 8, so 100% = 800. Approximation rule: in SBI PO answer options are spaced wide enough that rounding to 2 significant figures during multiplication is safe.

A table gives employees in 5 departments and the % who are female. Dept A: 250 total, 40% female. Female = 0.40×250 = 100, male = 150. If asked 'female in A as % of total female across all depts (say total female=520)': 100/520×100 = 19.23%. Key habit: compute the absolute female/male counts ONCE for all departments at the start (margin notes), because linked questions reuse them. For ratio questions like male in A : female in B, plug the pre-computed numbers directly. This pre-processing converts a 6-question set from 12 minutes to about 6 minutes — the single biggest time saver in tabular DI.

Bar graphs show discrete comparisons; line graphs emphasise TREND over time. First read the axis scale and unit — SBI PO loves dual-axis charts where one series is in Rs cr and another in %. For stacked/grouped bars, each segment is a separate value; total = sum of segments. For line charts, a STEEPER slope means a larger change, not a larger value. Common question types: difference between two bars, ratio of two points, average over a period, percentage growth between two years. Speed habit: estimate from the gridlines first to eliminate 2 distant options, then compute precisely only between the 2 close ones. Watch for 'between' (exclusive) vs 'from-to' (inclusive) in period questions.

Average over n periods = (sum of all values)/n. To find the value that makes a new average, use: required value = (new average × new count) − current sum. Percentage growth across a period from year1 to yearN = (valueN − value1)/value1 × 100 (NOT the sum of yearly growths). For 'overall ratio' across two series, sum each series first, then divide. CAGR shortcut (rare in prelims): for doubling, total growth = 100%. For difference questions, subtract directly from gridline readings. Mixed-unit trap: if a line shows % and a bar shows absolute totals, the actual value of the % series = (% reading) × (corresponding total).

A line chart shows a company's Revenue and Expenditure (Rs cr) over 4 years. Profit = Revenue − Expenditure. 2021: R=120, E=90 → Profit 30. 2022: R=150, E=100 → Profit 50. To find 'percentage increase in profit from 2021 to 2022': (50−30)/30 × 100 = 66.67%. If asked 'overall profit % over revenue for 2022': 50/150 × 100 = 33.33%. The trick: always compute Profit for every year at the start and write it above each point. Then 'average profit', 'highest profit year', and 'profit ratio' questions are instant lookups rather than fresh calculations.

A pie chart's full circle = 360° = 100% of the total. Conversion: 1% = 3.6°, and 1° = 5/18 %. To find a sector's value: (sector % or sector°/360) × total. SBI PO often gives ONE pie in degrees and another in percentages, or a pie plus a table — convert everything to a common unit first. Key memory aids: 90°=25%, 45°=12.5%, 60°=16.67%, 72°=20%, 36°=10%, 120°=33.33%, 180°=50%. To find the total when one sector's value and its angle are known: total = value × 360/angle. For 'central angle of X' questions: angle = (X value/total) × 360. Always confirm whether the question wants degrees, percent, or absolute value.

Mixed (or 'combined') DI pairs a pie with a bar, table, or line — or gives two interlinked charts. The skill tested is data transfer: a value from chart 1 becomes the base for chart 2. Workflow: (1) compute the grand total from whichever chart gives absolute figures; (2) convert all sectors/series to absolute values; (3) only then answer. Trap: percentages in two different charts are taken on DIFFERENT bases — never add raw percentages across charts. For 'X in chart A as % of Y in chart B', compute both absolute values first. Time tip: in a 5-question mixed set, the first 2 minutes spent building a small absolute-value table pays back across all questions.

A pie shows a family's monthly budget of Rs 48,000 split as: Food 30%, Rent 25%, Education 20%, Savings 15%, Misc 10%. Food = 30% × 48000 = Rs 14,400. Education = 20% × 48000 = Rs 9,600. 'Central angle of Rent' = 25% × 360 = 90°. 'Rent is how much more than Misc': Rent 12,000 − Misc 4,800 = Rs 7,200, or as % = (25−10)/10 × 100 = 150% more. If a second pie splits Food into items, multiply: e.g. Vegetables = 40% of Food = 0.40 × 14,400 = Rs 5,760. Note the chained calculation — Food's value feeds the sub-pie.

Caselet DI gives data as a PARAGRAPH with no chart — the hardest SBI PO format. Strategy: read once, then build your OWN table or Venn diagram from the text. Underline every number and its label. Watch linking words: 'remaining', 'rest', 'twice', 'half of', 'one-third more than'. For two-variable problems set up equations: if 'A is 20 more than B and A+B=180', then B=80, A=100. For set-based caselets (people who like tea/coffee/both), draw a Venn: n(A∪B)=n(A)+n(B)−n(both). Memory aid: 'AT LEAST one' = union; 'EXACTLY one' = union minus both-region; 'neither' = total − union. Never attempt caselets in your head — the 90 seconds spent tabulating prevents re-reading.

For heavy calculation DI use successive-percentage netting: a rise of a% then b% gives net = a + b + (ab/100). E.g. +10% then +20% = 10+20+2 = +32%. A +20% then −20% = −4% (never zero). For fraction-of-fraction, multiply fractions before touching the base: 3/5 of 2/3 of 900 = (3/5 × 2/3) × 900 = 2/5 × 900 = 360. Digit-sum / first-digit approximation eliminates wrong options fast in 'find approximate value' questions. For ratios that must sum to a total, scale the ratio: if A:B:C = 2:3:5 and total = 4000, each part = 4000/10 = 400, so A=800, B=1200, C=2000. Always reuse the 'one-part value' across the whole question.

Caselet: 'A shop sold 540 items on Day 1. On Day 2 sales rose by 1/3. On Day 3 sales were 90 fewer than Day 2.' Day 2 = 540 × (1 + 1/3) = 540 × 4/3 = 720. Day 3 = 720 − 90 = 630. Total 3-day sales = 540 + 720 + 630 = 1890. 'Day 3 as % of total' = 630/1890 × 100 = 33.33%. 'Average daily sales' = 1890/3 = 630. The discipline: write Day1, Day2, Day3 in a column the moment you read each clause — by the time you finish the paragraph the table is done and every sub-question is a lookup, exactly the SBI PO time-saving habit.